“ Men of merit considerably above the common level, sometimes under-rate as well as over-rate themselves. Such characters, though not very dignified, are often, in private society, far from being disagreeable. ”
 Adam Smith, The Theory of Moral Sentiments (1759). copy citation

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“Those two vices being frequently blended in the same character, the characteristics of both are necessarily confounded; and we sometimes find the superficial and impertinent ostentation of vanity joined to the most malignant and derisive insolence of pride. We are sometimes, upon that account, at a loss how to rank a particular character, or whether to place it among the proud or among the vain.
Men of merit considerably above the common level, sometimes under-rate as well as over-rate themselves. Such characters, though not very dignified, are often, in private society, far from being disagreeable. His companions all feel themselves much at their ease in the society of a man so perfectly modest and unassuming. If those companions, however, have not both more discernment and more generosity than ordinary, though they may have some kindness for him, they have seldom much respect; and the warmth of their kindness is very seldom sufficient to compensate the coldness of their respect.” source